




import re

def clean_str(text):
#r='[’!"#$%&\'()*+,-./:;<=>?@[\\]^_`{|}~]+'
    r='[’!"#$%&\'()*+,-./:;<=>?@[\\]^_`{|}~\n。！，]+'
    line=re.sub(r,'',text)
    line = line.lower()
    return line





